Title (en)

APPARATUS FOR AND METHOD OF STABILIZING THE QUANTITY OF LIGHT OF A FLUORESCENT LAMP

Publication

EP 0460719 A3 19920826 (EN)

Application

EP 91114661 A 19880531

Priority

• EP 88108716 A 19880531
• JP 1507588 A 19880125
• JP 13900887 A 19870604

Abstract (en)

[origin: EP0295491A1] This invention relates to an apparatus for and a method of stabilizing the light output of a fluorescent lamp employed for illuminating an original to be duplicated or the like. According to this invention, the quantity of light reflected from fluorescent lamp by a reference plane is detected, when scanning of an original is started, to control tube current of the fluorescent lamp on the basis of a detection signal, to thereby perform feedback control so that a detected light quantity value reaches a constant value. When the detected light quantity value reaches a prescribed value, the feedback control is released and the detected light quantity value is held to control the tube current of the fluorescent lamp on the basis of the held detected light quantity value. Thus, the tube current of the fluorescent lamp is adjusted to be constant on the basis of the held detected light quantity value during a scanning interval for the original to be duplicated, whereby the quantity of light of the fluorescent lamp is stabilized.

IPC 1-7

G03G 15/052; H05B 41/392; H01J 61/52

IPC 8 full level

G03G 15/04 (2006.01); H01J 61/52 (2006.01); H05B 41/392 (2006.01)

CPC (source: EP US)

G03G 15/04036 (2013.01 - EP US); H01J 61/52 (2013.01 - EP US); H05B 41/3922 (2013.01 - EP US)

Citation (search report)

• [A] US 4117375 A 19780926 - BACHUR GERALD, et al
• [A] US 4124294 A 19781107 - NAKAMURA YOSHIHIRO
• [A] US 4533854 A 19850806 - NORTHRUP KARL A [US]
• [A] US 4529912 A 19850716 - NORTHRUP KARL A [US], et al
• [A] PATENT ABSTRACTS OF JAPAN vol. 10, no. 282 (P-500)(2338) 25 September 1986 & JP-A-61 102 659 ( RICOH ) 21 May 1986
• [A] PATENT ABSTRACTS OF JAPAN vol. 10, no. 41 (P-429)(2098) 18 February 1986 & JP-A-60 186 828 ( FUJI XEROX ) 24 September 1985
• [A] XEROX DISCLOSURE JOURNAL vol. 10, no. 5, September 1985, pages 297 - 298; CORONA: 'FLUORESCENT LAMP ILLUMINATION CONTROL'
• [A] PATENT ABSTRACTS OF JAPAN vol. 8, no. 144 (P-284)(1581) 5 July 1984 & JP-A-59 042 534 ( FUJI XEROX ) 9 March 1984

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0295491 A1 19881221; EP 0295491 B1 19930818; DE 3854653 D1 19951207; DE 3854653 T2 19960321; DE 3883302 D1 19930923; DE 3883302 T2 19940331; EP 0460719 A2 19911211; EP 0460719 A3 19920826; EP 0460719 B1 19951102; US 4870454 A 19890926

DOCDB simple family (application)

EP 88108716 A 19880531; DE 3854653 T 19880531; DE 3883302 T 19880531; EP 91114661 A 19880531; US 20298588 A 19880606